The present invention is concerned with an efficient process for preparing .alpha.-vinyl substituent-.alpha.-amino acids and esters and certain intermediates.
Certain .alpha.-vinyl-.alpha.-amino acids can be prepared by reducing the corresponding .alpha.-ethynyl .alpha.-amino acid. Such processes are described in Tetrahedron Lett. 2745-2748; 3689-3692 (1977).
A more efficient process for preparing .alpha.-vinyl-.alpha.-amino acids and esters has been discovered.